Just as the question of who will play the next Time Lord grips millions, so there is a brilliant tension and uncertainty at the heart of British politics

Peter Capaldi may be very different to the last doctor - but that's precisely the point

THE genius of both Doctor Who and democratic politics is the potential for regeneration.

David Tennant played the Doctor brilliantly but his devoted fans knew a moment would come when he would vanish and a new actor would inherit the sonic screwdriver. This gave his splendid tenure a sense of tension and the public knew to enjoy it while it lasted.

Tennant’s successor, Matt Smith, was a radically different actor – and Peter Capaldi will take the role in bold new directions.

The fact that the Doctor routinely regenerates means that none of these great actors has had to perform an impersonation of the first man to hold the role, William Hartnell. Contrast this with the long shadow that Sean Connery casts over the James Bond franchise.

Barrel-chested Bond actors must play a character who looks terrific in a tuxedo and strides with imperial confidence if the role is to ring “true”. But anyone who has the honour of getting cast as the Doctor has extraordinary freedom to reinvent the role – the audience actually want to be surprised.

Regardless of whether the public like what he – and one day maybe she – does with the role, for better or for worse a bona fide Doctor is on the screen.

Just as my many Doctor Who-devoted friends are gripped with excitement when it is time for a regeneration, a similar sense of drama and sometimes renewal is felt during reshuffles and when election results come through. There is always a prime minister and a chancellor but shockingly different people can win the role.

When you look at the line of Welsh Secretaries who have won the keys to Gwydyr House, is this list any less eclectic than the roll-call of Doctors? One moment we had Peter Hain, then there was Cheryl Gillan; she was reshuffled to be replaced by David Jones, who was dramatically succeeded by Stephen Crabb.

The real suspense surrounds the question of who will step into the role of prime minister. This has only heightened in the coalition age.

In the wake of the 2010 elections, Gordon Brown fought to hold onto this great office of state but when the Tories struck their deal with the Lib Dems the Labour leader ceased to be PM and David Cameron his place. The son of the Manse was replaced with a spirited young dad.

Doctor Who fans toss around ideas for who should gain control of the Tardis – Idris Elba and Sheridan Smith were mentioned as possible candidates before Capaldi won out – and no less energy is devoted to speculation as to who the next party leaders will be. Politicians have fans of their own who are excited about what he or she might bring to an office.

Ed Miliband’s admirers like his pugnacious intellectual spirit and believe he would take a radically different approach to government if he became PM. Looking further into the future, Chuka Umunna is considered a real contender to one day lead the party.

David Cameron has no intention of letting Labour near Downing St without an almighty fight. But just as devotees of Tennant’s Doctor Who knew that the actor would one day move on, so Cameron loyalists will also daydream about who should helm the Tories.

Home Secretary Theresa May would be a formidable candidate and George Osborne has friends in senior positions who could prove influential in the casting process.

Some politicians are their own fans and make no secret of the scale of their ambitions.

Boris Johnson gives a brilliant impression of being flustered when asked if he wants to lead the Conservatives but if he succeeds in getting back into the Commons chatter about his long-term plans will reach a new octane of frenzy.

The beauty of democracy is that such different individuals can be in the frame for positions that will shape the destiny of a country.

Churchill may be regarded by many as the greatest PM of modern times but this does not mean that candidates for the role must match his waistline and intonations. Clement Attlee might have slept in the same Downing St home that Churchill occupied but he worked to bring revolutionary change to Britain.

Just as millions of us watch the Doctor played by different actors battle the same Daleks, so prime ministers face the common challenges of lowering unemployment, generating growth and tackling injustice. Each era requires an individual with specific gifts, insights and passions.

It is telling that in the era of the X-Factor and multiple shows that put power in the hands of the audience the makers of Doctor Who did not give the public the final say on who should succeed Matt Smith. Likewise, the main parties have yet to throw open leadership contests to the entire UK electorate.

Such a day could come when parties calculate this would bring them electorate advantage. Giving everyone a vote could lead to millions of people feeling they have a direct connection with the party leader, or at least a sense that he or she is the people’s choice.

If such an approach was used in television, would we ever have had Doctors as idiosyncratic as Sylvester McCoy or the present incumbent? In politics, would Michael Foot or Margaret Thatcher have been entrusted with such near-sacred responsibility?

I reckon the public’s appetite for renewal and regeneration might surprise us. In Wales, Rhodri Morgan could never have been described as a clone of the telegenic Blair but it was his freewheeling and unruly spontaneity that won him affection beyond Labour ranks.

Just as generations have been thrilled at the sight of a new doctor emerging from the Tardis, the suspense of seeing who will walk into Downing St will keep millions of us up on election night.

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